The next-generation multimedia wireless communication systems which are recently being actively researched are required to process and transmit various pieces of information, such as video and wireless data as well as the initial voice-centered services. The 4th generation wireless communication systems which are now being developed subsequently to the 3rd generation wireless communication systems are aiming at supporting high-speed data service of downlink 1 Gbps (Gigabits per second) and uplink 500 Mbps (Megabits per second). The object of the wireless communication system is to establish reliable communications between a number of users irrespective of their positions and mobility. However, a wireless channel has abnormal characteristics, such as path loss, noise, a fading phenomenon due to multi-path, inter-symbol interference (ISI), and the Doppler Effect resulting from the mobility of a user equipment. A variety of techniques are being developed in order to overcome the abnormal characteristics of the wireless channel and to increase the reliability of wireless communication.
A current wireless communication environment is pursuing the diversity of communication methods and devices in order to satisfy different service requirements. In the next-generation mobile communication system, it is basically expected that a demand for data traffic will be rapidly increased, and thus a communication method of preventing a large amount of data traffic from being concentrated on one node is being developed. For example, there has been research carried out on a communication method of distributing traffic into a plurality of base stations or a plurality of nodes. From among them, a communication method using a heterogeneous network is one of the major subjects of research. The heterogeneous network basically refers to a communication environment where base stations each having relatively small service coverage coexist within the service coverage of the existing base station.
In the heterogeneous network communication environment, inter-cell interference (ICI) may occur between the base stations. In general, the ICI may affect femto user equipment or pico user equipment which is served by a femto cell or a pico cell, having small service coverage, from a macro cell. In order to solve the ICI problem, a time domain-based solution and a frequency domain-based solution were proposed. For the time domain-based solution, reference may be made to 3GPP -RAN WG1 #62bis R1-105750. The ICI, however, cannot be efficiently removed by only the time domain-based solution or the frequency domain-based solution.
There is a need for a method of efficiently solving the ICI problem between base stations in a heterogeneous network communication environment.